Seafood through Time: Predation as a Driver of the Bathymetric Distribution of Crinoids
Predation, arguably an important mechanism of natural selection, is thought to have played an especially significant role in the evolutionary history of crinoids. Crinoids are marine invertebrates with a very long evolutionary history (ca. 0.5 billion years). As obligate passive suspension feeders, crinoids use their arms to form a filter that captures particulate nutrients from seawater. Ecologically important traits thought to have evolved among some groups of crinoids due to predation include an increase in mobility from fully sessile to crawling to swimming; an ability to regenerate lost body parts; biochemical defenses that make them distasteful.